Security	Date	Code	Shares	Price	A/D	Owned after	D/I	Nature of ownership
Common Stock^F1,F2,F3,F5	Apr 19, 2017	P	550,000	$2.00	A	1,991,441	I	Through Ally Bridge LB Healthcare Master Fund Limited See footnote
Common Stock^F1,F2,F3,F4	holding	—	—		—	1,397,853	I	Through ABG II-SO Limited See footnote
Common Stock^F1,F2,F3,F6	holding	—	—		—	3,243,242	I	Through ABG SRNE Limited See footnote
Common Stock^F1,F2,F3,F7	holding	—	—		—	1,500,000	I	Through ABG Innovation-SO Limited See footnote

Table II — derivative securities

Security	Conv. / exercise price	Date	Code	Shares	A/D	Exercisable	Expires	Underlying	Underlying shares	Owned after	D/I
Warrants^{F1,F2,F3,F5,F8}	$8.50	holding	—	—	—	—	May 31, 2019	Common Stock	432,432	432,432	I
Warrants^{F1,F2,F3,F6,F8}	$8.50	holding	—	—	—	—	May 31, 2019	Common Stock	432,432	432,432	I
Warrants^{F1,F2,F3,F6,F9}	$8.50	holding	—	—	—	—	Jun 7, 2019	Common Stock	540,540	540,540	I

Explanation of responses

F1The Reporting Persons are making this joint, single filing because they may be deemed to constitute a "group" within the meaning of Section 13(d)(3) of the Securities Exchange Act 1934 as amended (the "Act").
F2The Form 4 is filed by and on behalf of each of the following persons (each a "Reporting Person"): (i) ABG II-SO Limited ("ABG II-SO"), a British Virgin Islands limited company, (ii) Ally Bridge Group Capital Partners II, L.P., a Cayman Islands limited partnership, (iii) Ally Bridge LB Healthcare Master Fund Limited ("ABG LB"), a Cayman Islands limited company, (iv) Ally Bridge LB Management Limited, a Cayman Islands limited company, (v) ABG SRNE Limited ("ABG SRNE"), a British Virgin Islands limited company, (vi) Ally Bridge Group Innovation Capital Partners III, L.P., a Cayman Islands limited company, (vii) ABG Management Ltd., a Cayman Islands limited partnership, (viii) Mr. Fan Yu, a director of ABG LB and a shareholder and director of Ally Bridge LB Management Limited, and the sole shareholder and director of ABG Management Ltd., and (ix) Mr. Bin Li, a director and executive officer of ABG LB and a shareholder and director of Ally Bridge LB Management Limited.
F3Each Reporting Person states that neither the filing of this statement nor anything herein shall be deemed an admission that such person is, for the purpose of Section 16 of the Act or otherwise, the beneficial owner of any securities covered by this statement. Each Reporting Person disclaims beneficial ownership of the securities covered by this statement, except to the extent of the pecuniary interest of such person in such securities.
F4ABG II-SO directly owns 1,397,853 shares of common stock of the Issuer. The following Reporting Persons may be deemed to beneficially own such securities: (i) Ally Bridge Group Capital Partners II, L.P., as parent of ABG II-SO, (ii) ABG Management Ltd., as manager of Ally Bridge Group Capital Partners II, L.P., and (iii) Mr. Fan Yu, as sole shareholder and director of ABG Management Ltd.
F5ABG LB directly owns (i) 1,991,441 shares of common stock of the Issuer and (ii) warrants to purchase 432,432 shares of common stock of the Issuer. The following Reporting Persons may be deemed to beneficially own such securities: (i) Ally Bridge LB Management Limited, as manager of ABG LB, (ii) Mr. Fan Yu, as a shareholder and director of Ally Bridge LB Management Limited, and (iii) Mr. Bin Li, as a shareholder and director of Ally Bridge LB Management Limited.
F6ABG SRNE directly owns (i) 3,243,242 shares of common stock of the Issuer and (ii) warrants to purchase 972,972 shares of common stock of the Issuer. The following Reporting Persons may be deemed to beneficially own such securities: (i) Ally Bridge Group Innovation Capital Partners III, L.P., as owner of the sole voting share of ABG SRNE, (ii) ABG Management Ltd., as manager of Ally Bridge Group Innovation Capital Partners III, L.P., and (iii) Mr. Fan Yu, as sole shareholder and director of ABG Management Ltd.
F7Ally Bridge Group Innovation Capital Partners III, L.P. is the owner of the sole voting share of ABG Innovation-SO Limited, a British Virgin Islands limited company, which directly owns 1,500,000 shares of common stock of the Issuer. The following Reporting Persons may be deemed to beneficially own such securities: (i) Ally Bridge Group Innovation Capital Partners III, L.P., (ii) ABG Management Ltd., as manager of Ally Bridge Group Innovation Capital Partners III, L.P., and (iii) Mr. Fan Yu, as sole shareholder and director of ABG Management Ltd.
F8The warrants are exercisable at any time on or after May 31, 2016.
F9The warrants are exercisable at any time on or after June 7, 2016.